John desmond



(ModeL) J. DESMOND. INJECTOR.

No. 526,918. Patented Oct. 2,1894.

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UNITED STATES PATENT OFFI E.

JOHN DESMOND, or DETRom Iom n ASSIGNOR TO THE PENBERTHY INJECTORCOMPANY, OF SAME PLACE.

T'YIINJEICTO'R.

SPECIFICATION forming part of Letters Patent No. 526,918, dated October2, 18 94. Application filed April 10,1894. Serial No.50'7,016. (Model)To aZZ whom it may concern:

Be it known that I, JOHN DESMOND, a citizen of the United States,residing at Detroit, in the county of Wayne and State of Michigan, haveinvented certain new and useful Improvements in Injectors, of which thefollowing is a specification, reference being had therein to theaccompanying drawings.

The invention refers more particularly to a new construction,combination and arrangement of devices for enabling the injector tostart and restart automatically with absolute certainty; further, in theconstruction and operation of a movable steam nozzle arranged to operateas a steam and water valve, and further in the specific arrangement ofthe valves whereby they will not only stand the excessive wearnecessary, for instance, in a locomotive injector, but also permit theinjector to continue to work if the valves should become leaky. h p

Figure 1 is a vertical central section of an injector embodyingmyimprovement. Fig.2 is a cross section thereof on line a: a: Fig.1;Fig. 3 is a perspective view of the packing rings of the steam tube,detached.

The outer casing or shell comprises a horizontal portion A and avertical arm A' the former being provided with open branches B, C and Dfor connecting the injector with the steam and water supply and with theboiler as in the usual manner. Partition walls E F and G divide thiscasing interiorly into a steam chamber H, a water chamber I, an.

overflow chamber J and a pressure chamber K and these chamberscommunicate with each other through the steam tube L, the lifting tube Mand combining and discharge tube N, which are secured in the partitionwalls E, F and G respectively.

The tubes M and N are fixed and the steam tube slides for the purpose ofcontrolling the admission of steam and water in thef'ollowing manner:The rear end of the steam tube has aswivel connection with a screwthreaded valve stem 0 which engages in a screw plug rings 1) c. The ringb is conically reduced at one end and provided with a recess -b' intowhich the ring '0 is engaged. The two rings are split open, with thesplit ends located on opposite sides when the rings are in position. Thepacking ring I) is held in place by means of a loose collar 01 which isconically recessed to fit against the conical end of the packing ring b.The collar d is held in placeby a spring e and the spring is held inplace by a collar f, which is screw threaded into the box a. The rearend of the box a terminates in a valve seat 9 and the rear end of thesteam tube has an ofiset h whereby said rear end formsthe valve for theseat. Steam admis sion ports h are provided near the rear end of thesteam tube to admit steam from the steam chamber Hinto the steam tubewhen the shoulder h is withdrawn from the valve seat. f

The front end of the steam tube is adapted to closely approach the rearend of the mouth of the lifting tube, when the rear end of the steamtube is closed 'to' the entrance of the steam, the steam tube thusforming at the same time the valve for'regulating the admission of steamand water whereby separate valves for this. purpose are dispensed withand the construction and operation are thereby greatly simplified.

The arm A of the casing communicates at its lower end through a valveport Q with the overflow chamber J atits upper end it communicatesthrough passage K with the pressure chamber K and between the two endsit communicates through the exhaust chamber R with the overflow branchR. There are three valves S, T, and U located in this arm in uprightpositions, one above the other. The upper or pressure valveUis seatedupon a valve seat formed-on the upperend of a bushing c removably heldin place "by a hollow screw plug j which 'forms the pressure chamber Kon top of the valve communicating through ports j with the pressurechamber K. The lower or vacuum valve S controls the valve port Q and isguided in its movement bya stem S engaging in the'guide bearingformed inthe intermediate valve T. The intermediate valve or plunger T is locatedbetween the exhaust chamber R and" ICC the valve S and forms a waterseal chamber V between the two valves. The plunger has a shoulder 70around its upper end by means of which it is seated on a valve seat Zformed by an apertured partition m through which the plunger passes. Theupper side of the plunger is cup shaped and a pin hole n is placed inthe bottom of the cup. Both the valves T and U have wings to guide themin their vertical movements and these wings extend in close proximity toeach other as shown.

In practice, the parts being arranged, (5011-.

structed and shown as described the whole operation of starting theinjector consists in gradually retracting the steam tube by turning thevalve stem 0. In turning it to open, the valve formed on the steam tubelifts up from its seat It and admits the steam into the tube and fromthere into the injector. The pressure of the steam acting against theunder side of the valve S lifts up that valve and admits the steam intothe chamber V and acting against the under side of the plunger T liftsthe latter off from its seat and this in turn will lift the valve U,thus giving to the steam a free exhaust, and driving out the air. Thevalve U is made suitably smaller so that there is a preponderance ofpressure for lifting the valves against the pressure of steam acting ontop of the valve U, and if desired the stem S of the lower valve may bemade to impinge against the plunger T so that, in opening, it lifts boththe valves T and U off their seats. In

withdrawing the steam tube to admit steam to the injector the forwardend of the steam tube operates as a water valve and controls theadmission of water into the lifting tube (after the air is exhausted) inproportion to the amount of steam admitted into the rear end of saidtube. The water drawn into the lifting tube first escapes into thechamber J, from there into the chamber V and thence into the overflowbranch and as the stream gradually establishes itself through thecombining and discharge cone it will also find its way from the pressurechamber K through the passage K into the chamber K and from there out,past the valve U, into the overflow. As the jet gradually becomesstronger the pressure of the water in the pressure chamber willgradually increase and that in the vacuum chamber J will graduallydecrease. The valve U cannot close because it is upheld by the valve Twhich in turn is upheld by the pressure of the overflow against itsunder side (or against the under side of the valve S). As soon as theoverfiowinto the chamber J ceases (or nearly so) the valves S and T arefree to close, but while the valve S drops immediately to its seat, thevalve T being in form of a plunger, cannot do so becauseof the chamber Vbeing full of water which cannot get out except as it is graduallydisplaced around the plunger into the overflow. This delays the closingof the valve T and consequently of the valve U. As the stream passingthrough the combining and delivery tube cannot enter the boiler untilits force is sufficient to overcome the boiler pressure (there being theusual check valve between the boiler and delivery branch D) the delay inthe closing of the valve U keeps the overflow from the chamber K openand therefore the stream can fully establish itself into the deliverychamber before it meets with the boiler pressure, but when it hasobtained sufficient force the pressure of the incoming water actsagainst the valve U and the latter thereforerforces the valve T to itsseat and both valves become seated and the stream will force its wayinto the boiler. Should from any cause the stream become broken, thepressure of the steam would again open the valves S, T, and U and thestream would re-establish itself in the same manner as before described.

The operation of the valve U makes the injector start and restartautomatically with absolute certainty and in less time than it wouldrequire otherwise. As the pressure valve U and plunger T open and closetogether it is obvious that they may be united together. However it ispreferable to make them separate for the reason that they can be betterfitted to their seats.

My invention in regard to the construction and operation of the overflowvalves consists broadly in controlling the seating of the pressure valveby a water check, by which I mean a valve which is prevented from comingto its seat immediately by a cushion of water.

It is well nigh a practical impossibility to make injector valvesabsolutely tight, as there are so many difficulties to contend with. Inparticular the action of chlorides, which in some water are alwayspresent, becomes particularly destructive on the valves when the wateris boiling hot. Carbonic acid gas is quite as destructive on the zinc,tin, lead, copper and other metal in the composition for the valves, andthus by the corrosion of these metals, a leakage is produced in a shorttime. This leakage being thus diflicult to prevent, I propose takingcare of it in this way, placing the valves in an upright position, theleakage from the pressure valve will fall in the cup-shaped recess onthe top of the plunger T. From there it will leak through the pin-hole ninto the water chamberVfrom which in turn, if the valve S leaks, it willbe drawn in by the vacuum into the chamber J and thus pass into theinjector tube.

The expedient of controlling the seating of the valve U by a Water checkprevents it also from being damaged, as it would otherwise seat with ablow.

The same difliculty as to leakage is connected with the use of a movablesteam tube. This difficulty however I have overcome by the use of thepeculiar packing described. It

will be seen that the two packing rings 72 G are held by the steampressure against the end wall of the box a and around the steam tube,and as the rings are split open they are free to contract and fit tightaround the steam tube.

What I claim as my invention is- 1. The combination with the overflowchambers of the combining and delivery tubes of the injector and theoverflow branch into which said chambers separately communicate, ofvalves interposed between said overflow branch and said overflowchambers, and cooperating to automatically control the overflow fromsaid chambers into the overflow branch, and a water check applied to thevalve controlling the overflow from the delivery tube, substantially asdescribed.

2. In an injector, the combination with the casin g containing separateoverflow chambers for the combining and delivery tubes, of a vacuumvalve adapted to be unseatedby the pressure of the overflow from thecombining tube, an intermediate valve or plunger adapted to be unseatedby the pressure of the overflow from the vacuum valve, and a pressurevalve adapted to be unseated by theintermediate yalve and seated by thepressure of the overflow from the delivery tube under the control of theintermediate valve acting as a water check, substantially as described.

3. In an injector, the combination with the casing containing separateoverflow chambers for the combining and delivery tubes, of the vacuumvalve, an intermediate valve or plunger, and a pressure valve containedin a vertical arm of the casing one above the other, a pressure chamberformed in the arm of the casing above the pressure valve andcommunicatin g with the overflow chamber of the delivery tube, anintermediate valve chamber between the pressure valve and theintermediate valve or plunger, and communicating into the overflowbranch of the injector, and a lowervalvechamberbetweenthe intermediatevalve and the vacuum valve and com municating through a port controlledby the vacuum valve with the overflow chamber of the combinin g tube,said valves operating as set forth to automatically control each otherin seating and unseating, substantially as described.

4. In an injector, the combination with the casin g containing separateoverflow chambers for the combining and delivery tubes, of the verticalarm A communicating with said overflow chambers and provided with anoverflow branch R, the valves T and U in said arm interposed betweensaid overflow chambers and the overflow arm, and the vacuum valve Sinterposed between the valve T, and

the overflow chamber of the combining tube, and co-operating with thevalve T to unseat the valve U by the pressure of the overflow from thecombining tube, and to form a water check to delay the seating of saidvalve against the pressure of the overflow from the delivery tube,substantially as described.

5. In an injector, the combination of the easing A, the overflowchambers K and J the vertical arm A of the casing communicating with theoverflow chambers K and J and with the overflow branch R, the valves U,T and S contained in said vertical arm one above the other andco-operating as set forth to seat and v unseat automatically, the cup orrecess on top of the intermediate valve T and the pin hole 11 in thebottom of said cup, substantially as described.

6. The combination with the casing and par tition separating the steamand water chambers of the injector, of a movable steam tube, extendingthrough a stuffing box in said partition and adapted to form a watervalve, lateral steam admission ports into the steam tube, and a valveseat around the rear end of the steam tube adapted to seat against therear end of the stuffing box to form a steam valve for admitting thesteam into the lateral ports of the steam tube, substantially asdescribed.

7. The combination with the casing and partition separating the steamand water chambers of the injector, of the movablev steam tube Lprovided with two valve seats adapted to form the steam and water valveof the injector as described, and a stuffing box consisting of the boxa, the split rings b c,the collars df and the spring e interposedbetween the collars, all arranged to operate substantially as described.

In testimony whereof I aftix my signature in presence of two witnesses.

JOHN DESMOND.

Witnesses:

JAMES WHITTEMORE, M. B. ODOGHERTY.

